what is purpose of command smove in redis?

Question

in redis for moving on set collection to the another set collection we can use "smove" command as

bellow :

smove set1 set2 member

and my question is this operation , solve what`s problem . if someone has good answer , tell me please

Answer 1

Without this command you would have to remove and item from set1 and add it to set2.

This is not atomic.

If your process died in the middle you would lose that set entry before it was added to set2

https://redis.io/commands/smove has more information